Family Lycaenidae

Harvesters, Coppers, Hairstreaks, and Blues

This large family has about 4,000 species worldwide, with about 150 in North America and 63 in Canada. All are small and most are brightly coloured, often with a metallic sheen. Many have fine hair-like tails on the hindwing. The legs of the adults are unusual in that the male's forelegs are reduced in size and lack claws, while the female's are normal in size and structure.

The larvae are also unusual. They are not elongated and cylindrical, like most lepidopteran larvae. They are often described as slug-like, but even this is not accurate; slugs are more elongate than lycaenid larvae. More than anything they resemble a wood-louse (sowbug) in shape: somewhat flattened dorsoventrally, and three to four times as long as wide. Larvae of many species have glands that produce a sweet honey-dew secretion attractive to ants, which tend them in exchange for these secretions and offer important protection against predators. They feed on many families of dicotyledonous plants, often eating only the flowers and seeds. Some, including the Harvester, are carnivorous, eating aphids or other insects. Most species hibernate in the egg or pupa stages.

Subfamily Miletinae


This is a small, mainly African and Oriental, subfamily. The larvae are peculiar in that they are carnivorous, feeding on other insects such as aphids and other homopterans. The single North American representative of the subfamily, the Harvester, feeds exclusively on aphids.

Subfamily Lycaeninae


This subfamily of mostly metallic-red or orange butterflies occurs mainly in the Northern Hemisphere, although there is one species in South America and three in New Zealand. There are about 20 species found in North America and 12 in Canada. The American Copper (Lycaena phlaeas)occurs far up into the Arctic on Ellesmere Island.

The adults are avid flower visitors and often rest with their wings held open, reflecting sunlight with a metallic, often purplish, sheen. The males of most species are territorial and aggressive and have a fast, erratic flight. Although found in all provinces and territories, they tend to be local in distribution, many associated with wet areas such as bogs or swamps.

The eggs are placed by the female on the underside of the leaves of the foodplant and they usually overwinter in this stage. In some species the larva forms in the egg and then overwinters in this condition.

Subfamily Theclinae


This is the largest subfamily of Lycaenids. They are found on all continents, and are most numerous in the tropics, especially in the New World. About 90 species are found in North America and 31 in Canada. Many are local, with restricted distributions that extend into southern Canada, and a few have been recorded only as strays, mainly in southern Ontario.

The majority of our species are dark brown on the upper surface, but a few have a blue iridescence reminding us of their tropical relatives. Many also have one or two hairlike tails on the hindwing and most have wavy or broken lines on the lighter coloured undersurface, likely giving rise to the common name of hairstreak. Often there is a dark spot, called a "thecla spot", above the tails on the undersurface. Many species perch upside-down, so that the thecla spot resembles an eye and the tail looks like an antenna. All Canadian species sit with their wings folded tightly over their backs, and often rub the hindwings together to move the tails in a manner even more resembling antennae. It is conjectured that this is a defensive mechanism to lure a would-be predator to the hind end of the butterfly. Any resulting damage would likely not be fatal, allowing the butterfly to fly off, damaged but still alive. It is not uncommon to find hairstreaks with tears or beak-marks where the tails should be.

Most members of this subfamily are fast flyers and visit flowers regularly. The males often perch on leaves waiting for females. When startled, they zip away, often to alight again on the same leaf. Males of many species have a sex pad near the front edge of the forewings; these pads contain special androconial scales that produce a smell important in courtship. The eggs are laid singly on the foodplants, in the case of species that hibernate as eggs, on woody twigs or overwintering buds so as to avoid being shed with the leaves in the fall. The larvae feed on the leaves, flowers, or fruits of a wide variety of plants, mainly trees or shrubs. Many hairstreaks (e.g., Satyrium spp.) in Canada overwinter in the egg stage, while others, including the elfins (Callophrys spp.), hibernate as pupae.

Subfamily Polyommatinae


This is a large worldwide subfamily, with about 40 species in North America and 19 in Canada. In almost all species males are blue, while females have varying amounts of brown or grey partially, or sometimes completely, obscuring the blue colour. They also have a complex pattern of dark spots and bands on the underside. They have rounded wings and most are weak fliers, regularly seen on flowers or hovering around the foodplants. Very few migrate, but our first two species have been taken in Canada only as a result of longer-than-usual migratory flights. The eggs are laid singly on flowers or buds, and the larvae of all Canadian species eat flowers and fruits of the foodplants. These are usually Fabaceae (Leguminosae), although there are exceptions. Hibernation can be as an egg, larva, or pupa in different species.

© 2002. This material is reproduced with permission from The Butterflies of Canada by Ross A. Layberry, Peter W. Hall, and J. Donald Lafontaine. University of Toronto Press; 1998. Specimen photos courtesy of John T. Fowler.